This book is published by the Mineralogical Association of Canada in collaboration with ORSTOM (Office de la Recherche Scientifique et Technique Outre-Mer). It is thus fitting that Prof. R.F. Martin, editor of Canadian Mineralogist, should write a ‘Preamble’, in which he notes that this book forms a bridge between the fields of classical mineralogy and soil science. Because of the much increased interest in ‘the environment’, this cross-fertilization of ideas is becoming more necessary than ever. This is very much a book on the weathering of igneous and metamorphic rocks in tropical climates which the author has studied since...